The present invention relates to clocks, more particularly to a structurally improved pendulum and the housing of a clock which are suitable to develop an ultrathin
Prior art electromagnetic clock (as shown FIG. 1) in the type comprises generally a housing 10 and a pendulum 20, where the housing 10 is partitioned of a median chamber 101 for disposing a set of clockwork mechanism therein, a lower chamber 102 for receiving an electric circuit and batteries therein and an upper chamber 103 for pivoting the pendulum 20 thereon. Whereas, the pendulum 20 has an elongate body, a tubular hook 201 formed perpendicular to the upper end, a small cup 202 for retaining a rectangular magnet 203 therein connected to the lower end thereof and a hook means 204 for suspending a bob positioned under the receiving space 202.
When the pendulum is anchored on a knife-edge pivot axis inside the upper chamber 103 and fixed by a cover 104, the rectangular magnet 203 on lower end of the pendulum 20 is just under an electric coil inside the lower chamber 102 so as to activate the pendulum 20 to vacilate laterally with the bob by the variation of the magnetic field thereof. To prevent the pendulum 20 from being obstructed by the back side of the housing 10, a outward slope is formed in the proximing of its upper end in an intention to maintain an adequete space between the pendulum 20 and the housing. Therefore, the housing 10 of the clock must maintain a considerable thickness, which is a fatal disadvantage to develop an ultrathin electromagetic clock.